Hygrostat or thermostatic device.



W. H. CARRIER.

HYGROSTAT 0R THERMOSTATIC DEVlCE. T1011 man MAY 2e. 1910. M NEWED PEB.20. 1914.

APPLICA l Patent-ed May 4,1915;

SASHEETS-SHEET I.

W. H. CARRIER. HYGROSTAT 0R THERMOSTATIC DEVICE. APPLICATION FILEDMAY'ZB, 1910- RENEWED FEB. 20, 1914.

1,138082. Patented May 4,1915.

a SHEETS-SHEET a.

loto

'. comprises two per cents of hygrostatic' cbnditions.

.TQ all whom t mag/ concern:

r Vice which isactuated by t -action of said WILLIS IH. CARRIER, OFBUFFALO,

NEW YORK, 0F BUFFALO, NEW YORK.

.ASSIG-NO TO BUFFALO FBRG'E COMPANY,

L HYGROSTAT 0R THERMOSTATIC DEVICE.

applicaties sied tray 26, 1910, serial No. 563,509.

that .1, WILLIS H. CARRIER', a citizen yof the United `States, residingat Bualo, in the county of rie and State of ew York, have invented n "tnew and' useful mprovement in Hygrostats evices, of which the followingis a specification.

Be it known An instrument offthiS character is disclosed in theapplication for United StatesV patent'iled by myself andvE. W. CSeptember 28, 1908, Serial No.455,208,wh1ch expansible or elementaoneinfluenced by the actual or dry bulb temperature of the air and theother influenced by the lower Wet bulb temperature of the air producedby evaporating moisture in its vicinity, and a humidity'regulating dehe.diiierential p expansible elements. .The fluctuations in the dry and Wetbulb tempera:l tures of the. air, which takeplace while theliiekarcentage of humidity remains constant,

ear a practically fixed relation or radio to other within ordinaryrangesr of temthe radios did'er for different humidity, Likewise, theratio of iluctuationsin the dry and pera'tures of the air remains V eachperature, but

the instrument l l the expansible elements have t ,8

letting device through a lever tions to each other corresponding todifferent ratios of changes in the dry and Wet bulb temperatures of theair, whereby the instru- `to produce ldiilerent desired rlhe object ofthis invention is to produce an accurate and reliable hygros'tat orthermostatic instrument of lthe nature stated, which is out simple. andpractical construction and which can be quickly and easily set toproduce dieient the actuation lInidty of the air, or Th'ermostatic of,on an enlarged scale. verse Sectional elevati-onthereof, on an en- Fig.6- is a transverse diseased in Stia appiiciaon fi'licients of expansionand actuate the reguthe dry and. Wet

coelicient of required results by v Specification of Letters Patent.

Patented May d, 1915'. Renewed February 20,` 1914. Serial No. 820,065.

of 'a single adjusting screw or device.-

The insti-merit emmener described is primarily intended for regulatingthe hubut the 'invention isnot necessarily restricted tol humidityregulatasthe motion of the' device tary longitudinal Sectionalelevationy there- Fig-..5 is a translarged scale, in line 5-5, Fig. l.sectional elevation thereof on an enlarged scale, in line 6-6, Fi 2. 7is a detail section in line 7- Fig. 4. Fig. 8 is a fragmentaryperspective view of the connecting lever for vthe expansible elementsandassociated parts.

Like reference characters parts the Several figures.

vA and B represent the two thennostatic or expansible elements which trerespectively subjected to the actual, or dry bulb, and the temperaturesof th after describe or convenience are hereinafter termed elements,respectively. One element, referably the wet element B, may consistasingle tube or piece of hard rubber or other suitable material having acoeiiicient of expansion. The other,.or shown in Fig. ,4, consistsv ofsimilar material expansion, and a rod 2 which has such a low coefiicientof expansion that it is relatively non-expansible. screw-threaded andrig..

refer to like i havin a Yhigh y This rod i. works in a stationarynon-expansible nut a and has an end portion an internal screwso that byscrewing is screwed into 'in the tube A,

w thread expansion of the whole `2i?y naled in a bearing af on y 'thatthe wheel the rod A2` into or outof the tube the eective expansiblelengthofV the tube is' creased] or increased and the coeiciento element,consisting of the two parts A and A2,. is changed. The nut a;.preferably has; a guide cavity provided with an insulating ring a inwhich the adjacent endoi the tube A bears and is adapted .to slidefreely, while being held from turningby a key a2. rlhe nut also has aguide extension tion of the rod and is guided, whereby ,the two partsofthe dry element are 'properly supported and guided. The seifewzrodcould be turned by a finger wheel or part at its outer end, butpreferably a finger wheel a? is employed having a sha t c@ which issplined in the outer end of the screw A2. The linger wheel shaft vc isjourthe casing D ofthe instrument and is held from endwise movenienttherein, as-by a screw a7 extending into a -circumterential groove inthe shaft aP so or handle a4 for the screw does notmove lengthwise withthe screw when it is turned.

In the construction shown, the two expansible elements are arrangedparallel with eachother with one end of the wet element bearing by apoint or reduced part b against the regulating lever or device C,opposite en yoi the dry element bear against a pivoted lever or member Ewhich is held against the by a suitable spring C preferably consists oitwo parts independently v tulcrumed to posts or parts c of the casingdryV element A bears, an r.1..,having a pointed en .'whichliold the twoparts of lsockets in a wall or part f bythin spring plates c c2 thelever in contact and press the lever against the wet element. The leveror member E, as shown in Figs. t and 8, has two and e which are held byD respectively the spring F in of the casing D, in which a point e2 onthe end of the d an adjustable screw which bears in a socket on the endof the wet element. h e

spring F, which is connected at opposite a socket draws the lever Etoward' but permits to be moved in the opposite direction by theexpansion ofthe elements. The regulating lever or device C will remainstationary or be moved in one direction or the other, depending .uponthe relative changes in the lengths oi the two expansible elementscaused by changes in the temperatures adecting them.

lf the screw-thread of the adjustable part '-AZ and the internal threadof the part A of the dry element.

were of the same pitch `at all times, regardless of the change in as inwhich av smcothvporof the element and thel free end fulcrum points e fFurthermore, the

length of'the part A due to the expansion thereof' at differenttemperatures, the coeiiicient the comp d by screwing the part A2 into orout ,of the other part without any change in the eective expansiblelength of the dry element. But 'the pitch of the thread of the partclianges'with the expansion and contraction of this part, and since thewet bulb depression is diderent for diierent percentages o humidity atthe Vsame vdry bulb temperature, the relative lengths of the wet and dryelements will be different for different percentages of humidity.Therefore, when the relative coeiiicients of expansion o t e elementsare changed by adjusting the screw A? to obtain a desired percentage ohumidity, the relative lengths of the wet and dry elements must also beappropriately changed in order to obtain the proper regu lating actionof the lever or device By cutting A and 2 to such-a difference of pitchthat the ratio of the two pitches at any temperature is practically thesame as the ratio to each other of the wet and dry bulb temperatures, asreckoned Jfrom a predetermine xe oint or zero, which is dependent uponthe relative expans'bility of the elements, then at normal temperatures,for example, between 50 and 100 Fahrenheit, the adjustment. of the partA2 more or less into or out of the part A will change the relativeexpansive lengths of the two elements to the extent required Jfordierent percentages of humidity as well as changingthe ratio ofexpansion of the elements. When one part of the lcompound elemen lynonexpansible,

should be such as to have the same pitch at approximately 4 above zeroFahrenheit.

The adjustment of the relative lengthsof the wet and dry elements couldbe edected by adjusting the bearing screw e3 carried by the lever E, butby constructing the dry element as above described the turning of thesingle adjustablepart 2 adjusts for both the expansive length and thevexpansive ratio of the elements at one i adjustable part A2 of theelement has sufficient travel to allow the for various percentages ofhudry adjustments and the same. time.

midity to be indicated accurately upon a dial. l

The lever or device C could be dierently constructed and. mounted, andmeans o other construction could be employed for operatively connectingelementsv constructed as described. The free end of the regulating leverC acts as a valve to control a bleeder or escape orifice h, Figs. Ll and7', in a branch h of a pi e supplies compressed air to the actuatingdiaphragm or the ltwo exp ansible' H which motor of the apparatus (not vmovement of the lever.

larly actuated, can be employed for proj shown) which regulates thehumidity of the air. A` restricting-valve [t2 isprovided in the-air pipe.H which. permits only a very small quantity of air. tovpass;totheregulating motor. Ii the .bleeder malice is closed by theregulating device C the air pa can pass the restricting valve to themotor, thusv permitting the motor to eifect an op-l posite movement ofthe part actuated there by. Thus the regulating device C by opening andclosing the bleeder orifice it. acts, through the humidity regulatingapparatus, to effectv a change'in the humidity of the a1r.

The invention is not restricted to the means described whereby themovement of the regulating lever C effects the regulation, and otherinstrumentalities governed by the C, or other part simiducing a desiredresult. v

he means shown for causing the wet: element to be afected by'the wetbulbtemperature of th y wick I which surrounds the wet element and dipsinto water in a'receptacle i which 'is automatically replenished, as thewater 1s taken up by the wick, from a water reservoir i formed by alargezchamber in the rear portion of the casing D. Water can be'suppliedl to the reservoirand fed auto'- matically therefrom to thereceptaclez any usual or suitable-way, for described in saidapplication. s

The expansible elements A )and B are preferably located in an airpassagev formed by the walls f and f of the casing D and connectingwalls-lac', and air is'caused to circulate through this passage by anaspirator example, as

or other me evaporation of themoisture aroundthe Wet element.

sob

Other, suitable means could be used for subjecting. the 4wet element Bto the wet ulb'temperature of air. f

represents a pointer'or index which cooperates with a dial Z forindicating the correct adjustments of the instruments` for dii- .ferentpercentages of humidity. This index,

in the construction shown, is pivoted in the rear portion of the casingD and is connected by a link Z to a rod Z2 which slides in a guide tubeZ3. This rod is provided at one end with an adjustable screw l4 which isheld against a collar on the adjustable 'partAe of the dry element by aspring Z5 acting on the index. The index is shifted with the adjustablepart A2 of the dry element and by its position indicates vthe percentageoi humidity for which the instrument is set. Any

character described, the combination 'relative expansible length and th.Y sive ratio of' said elements e air consists of an absorbent;l

an'sto insure an activeother suitable means actuated by the adjustmantofthe part d? could be employed for this purpose.

` I claim as my invention:` I. In

.connectionshavingf threads which have the same pitch ay temperatureapproximately 3. In a thermostatic instrument lo f the characterdescribed, the combination ofltwo expansible eiements which arerespectiyely uenced by the dryand peratnres1 of. the air, one ofv saidelements' consisting of a-,diderential screw, the parts of. which have,d' pansion,

a device actuated bythe diii'erential action of said two expansibleelements, as set forth.

4. In a thermostatic character described, the combination oi` twoexpansible elements, means whereby one of said elements is subjected tothe temperature of th adjustable simultaneously, and a device which isactuated by the diierential action 'of said two elements, substantially-as set forth.

ln a thermostatic instrument of the character described, the combinationofv two expansible elements, said elements is subjected to the wet bulbtemperature of the atmosphere, one of said elements comprising two partshaving difof expansion, a support part of said having screw with saidother part of the element and with said support, the threads of d screwconnections having pitches such wet bulb temv substantially instrumentof the y means whereby one of,

a single adjustable j that the'a'djustinent of said adjustable partchanges the relative eXpans `the expansive ratio of said elementssimultaneously, and a device which is actuated by the differentialaction of said substantially as set forth. j

6. In` a thermostatic instrument of the character described, thecombination of two expansible elements which are subject to differenttemperatures and are arranged substantially parallel with each other,one of said elements com rising two parts which have different coecients of expansion and have a screw connection, asupport with which oneof said parts has a screw connection, a lever which bears against thefree end of said two-part element and against the adjacent end of the'other element, and a device whichbears against the opposite end lofsaid last mentioned element and is actuated thereby, substantially asset forth.

7.In a thermostatic instrument of the character described, thecombination of two expansible elements, means whereby one of saidelements is subjected to the wet bulb temperature of the atmosphere',one of said -elements comprising two parts having di ferent coeiiicientsof expansion, a support for said two-part element, one part of saidelement being adjustable and having screw connections with said otherpart of the element and with said support, the threads of said screwconnections having pitches such that the adjustment of saidadjustable'part ble lengths and j two elements,

ldifferential changes thefrelative expansible lengths and the expansiveratio of saidelements simultaneously, and a rotatable operating handlefor said adjustable part which' is held from endwise movement with saidadjustable part, substantially as set forth.

1.8. ln a thermostatic instrument of the character described, thevcombination of two expansible elements, means whereby one of saidelements is subjected to the wet bulb temperature of the atmosphere, oneof sai elements comprising two parts having different coefficients ofexpansion,v a support for saidtwoipart elementone part of said elementbeing adjustable and havingv screw connections with said other partofthe element and with said support, the threads of said screwconnections having pitches such that the adjustment of said adjustablepart changesthe relative expansible lengths and the expansive ratioof-said elements simultaneously, a device which is actuated by theaction of said two elements, and an index which is connected to andmoves with said adjustable part for indicating the adjustment thereof,substantially as set forth. A

Witness my hand this 23rd day of May,

j WILLIS H. CARRIER.

`Witnesses: v

EDWARD C. HARD, C. B. HoRNBEcK. l

